The conventional Laser-Two-Focus (L2F) method measures the twocomponents of the flow vector in the plane normal to the optical axis bymeasuring the time of flight of particles crossing the two laser beamsin the probe volume. Recently a new three component system wasdeveloped, named 3D-Doppler-L2F, which operates with the same confocaloptical set-up as the two component L2F system, thus enabling threecomponent measurements even under difficult conditions, for example incentrifugal compressors. The technique combines the L2F with thetechnique of the Doppler Global Velocimeter. The set-up of a3D-Doppler-L2F, especially designed for 3D-velocity measurements in aturbine is presented as well as measurement results from a freejet
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